The Binding of Pseudomonas aeruginosa to Cystic Fibrosis Bronchial Epithelial Model Cells Alters the Composition of the Exosomes They Produce Compared to Healthy Control Cells.

Cystic fibrosis (CF) is a genetic disease that causes dehydration of the surface of the airways, increasing lung infections, most frequently caused by Pseudomonas aeruginosa. Exosomes are nanovesicles released by cells that play an essential role in intercellular communication, although their role during bacterial infections is not well understood. In this article, we analyze the alterations in exosomes produced by healthy bronchial epithelial and cystic fibrosis cell lines caused by the interaction with P. aeruginosa. The proteomic study detected alterations in 30% of the species analyzed. In healthy cells, they mainly involve proteins related to the extracellular matrix, cytoskeleton, and various catabolic enzymes. In CF, proteins related to the cytoskeleton and matrix, in addition to the proteasome. These differences could be related to the inflammatory response. A study of miRNAs detected alterations in 18% of the species analyzed. The prediction of their potential biological targets identified 7149 genes, regulated by up to 7 different miRNAs. The identification of their functions showed that they preferentially affected molecules involved in binding and catalytic activities, although with differences between cell types. In conclusion, this study shows differences in exosomes between CF and healthy cells that could be involved in the response to infection.

Predictive value of computed tomography scoring systems evolution in adults with cystic fibrosis.

OBJECTIVES: To assess whether the evolution of two consecutive high-resolution computed tomography (HRCT) scores in patients with cystic fibrosis (CF) has prognostic value. METHODS: A longitudinal retrospective study was performed to research adult patients with CF. Two consecutive HRCT studies were scored using Bhalla and Brody II scoring scales by two senior radiologists. Annual scoring changes for each scale were calculated and correlated with annual FEV1% decline, with pulmonary exacerbations and number of antibiotic treatments. RESULTS: We selected sixty-four adult patients. The median interval between the two HRCTs was 3.88 ± 1.59 years. The mean spirometric values showed dynamic lung volumes lower than the general population; globally, there was a worsening of respiratory function over time. The change in the annual HRCT scores was positive on both scales, indicating a worse structural situation over time. The Brody II scale annual change showed a significant statistical correlation with a decline in the annual FEV1%, exacerbations and number of oral antibiotic treatments. In contrast, for the Bhalla scale, the relationship was moderately inverse with exacerbations and with the number of oral treatments. No statistically significant relationships were found for the change in the annual FEV1% and exacerbations or number of antibiotic treatments. The interobservational and intraobservational agreements were very strong in both scales. CONCLUSIONS: The annual evolution of the Brody II HRCT scoring system demonstrated a predictive value and correlated with FEV1% decline, pulmonary exacerbations and oral antibiotic treatments. KEY POINTS: • HRCT evolution has prognostic value in cystic fibrosis. • Temporal evolution for the Brody II score is useful for clinical follow-up. • Brody II score changes correlate with FEV1% decline, pulmonary exacerbations and number of antibiotic treatments.

Bronchiectasis: A Complex, Heterogeneous Disease. / Las bronquiectasias: una enfermedad compleja y heterogénea.

Most areas of respiratory medicine continue to use an Oslerian approach, based on signs and symptoms, in which the disease is the center of all activity. However, this paradigm is changing. Now that lung diseases have been recognized as heterogeneous and complex, we are moving towards more personalized, precise, patient-oriented medicine. The aim of this review was to define the current state of the knowledge on bronchiectasis, or, more accurately, the bronchiectasis syndrome, as a multidimensional, systemic, heterogeneous, complex disease. We explore the advances that have already been made, and above all the many steps that are still to be taken. We also propose some tools which might facilitate the application of these concepts in clinical practice, and help us continue our journey towards a more holistic view of this disease.

Glycosaminoglycans are differentially involved in bacterial binding to healthy and cystic fibrosis lung cells.

BACKGROUND: Glycosaminoglycans (GAGs) are essential in many infections, including recurrent bacterial respiratory infections, the main cause of mortality in cystic fibrosis (CF) patients. METHODS: Using a cellular model of healthy and CF lung epithelium, a comparative transcriptomic study of GAG encoding genes was performed using qRT-PCR, and their differential involvement in the adhesion of bacterial pathogens analyzed by enzymatic degradation and binding competition experiments. RESULTS: Various alterations in gene expression in CF cells were found which affect GAG structures and seem to influence bacterial adherence to lung epithelium cells. Heparan sulfate appears to be the most important GAG species involved in bacterial binding. CONCLUSIONS: Adherence to lung epithelial cells of some of the main pathogens involved in CF is dependent on GAGs, and the expression of these polysaccharides is altered in CF cells, suggesting it could play an essential role in the development of infectious pathology.

Addition of hyaluronic acid improves tolerance to 7% hypertonic saline solution in bronchiectasis patients.

BACKGROUND: The excessive retention of sputum in the airways, leading to pulmonary infections, is a common consequence of bronchiectasis. Although inhalation of 7% hypertonic saline (HS) has proven an effective method to help remove the mucus, many patients are intolerant of this treatment. The addition of 0.1% hyaluronic acid to HS (HS+HA) could increase tolerance to HS in these patients. The main objective of this study was to evaluate the tolerability of HS+HA in bronchiectasis patients who are intolerant to HS. METHODS: This prospective, observational, open-label study analysed the outcomes of two groups of bronchiectasis patients previously scheduled to start HS therapy. Patients were assessed for tolerance to HS by a questionnaire, spirometry and clinical evaluation. Patients who were intolerant were evaluated for tolerance to HS+HA approximately one week later. All patients were evaluated for their tolerance to HS or HS+HA 4 weeks after the start of their treatment. Patients were also assessed with quality-of-life and adherence questionnaires, and all adverse events were registered. RESULTS: A total of 137 bronchiectasis patients were enrolled in the study (age = 63.0 ± 14.7 years; 63.5% women). Of these, 92 patients (67.1%) were tolerant and 45 patients (32.9%) were intolerant to HS. Of the 45 patients intolerant to HS, 31 patients (68.9%) were tolerant and 14 patients (31.1%) intolerant to HS+HA. Of these 31 tolerant patients, 26 (83.9%) could complete the 4-week treatment with HS+HA. CONCLUSIONS: Two-thirds of bronchiectasis patients that presented intolerance to inhaled HS alone are tolerant to inhaled HS+HA, suggesting that HA improves tolerance to HS therapy.

Reversible Stereodivergent Cycloaddition of Racemic Helicenes to [60]Fullerene: A Chiral Resolution Strategy.

[60]Fullerene and its rarely explored reversible covalent chemistry have been harnessed as an efficient alternative for the chiral resolution of racemates. By using only catalytic amounts of chiral agents, stereodivergent 1,3-dipolar cycloadditions of racemic helicenes onto [60]fullerene were carried out. The formed helicene/fullerene diastereomers were easily separated by conventional chromatography, and afterward, a simple catalyzed 1,3-dipolar retro-cycloaddition afforded helicene starting materials in high optical purity.

On the regioselectivity of the Diels-Alder cycloaddition to C60 in high spin states.

Controlling the regioselectivity in the exohedral functionalization of fullerenes and endohedral metallofullerenes is essential to produce specific desired fullerene derivatives. In this work, using density functional theory (DFT) calculations, we show that the regioselectivity of the Diels-Alder (DA) cycloaddition of cyclopentadiene to 2S+1C60 changes from the usual [6,6] addition in the singlet ground state to the [5,6] attack in high spin states of C60. Changes in the aromaticity of the five- and six-membered rings when going from singlet to high spin C60 provide a rationale to understand this regioselectivity change. Experimentally, however, we find that the DA cycloaddition of isoindene to triplet C60 yields the usual [6,6] adduct. Further DFT calculations and computational analysis give an explanation to this unanticipated experimental result by showing the presence of an intersystem crossing close to the formed triplet biradical intermediate.

Cyclobuteno[60]fullerenes as Efficient n-Type Organic Semiconductors.

Cyclobuteno[3,4:1,2][60]fullerenes have been prepared in a straightforward manner by a simple reaction between [60]fullerene and readily available allenoates or alkynoates as organic reagents under basic and mild conditions. The chemical structure of the new modified fullerenes has been determined by standard spectroscopic techniques and confirmed by X-ray diffraction analysis. Some of these new fullerene derivatives exhibit a remarkable intrinsic electron mobility (determined by using flash-photolysis time-resolved microwave conductivity (FP-TRMC) measurements), which surpasses that of the well-known phenyl-C61-butyric acid methyl ester, thus behaving as promising n-type organic semiconductors.

Organocatalysis for new chiral fullerene-based materials.

The cycloaddition reaction of 3-alkynoates to fullerenes has been studied under different experimental conditions and phosphines in the presence of a base which is responsible for the previous isomerization to the corresponding allenoate. The versatility of this reaction allows chiral fullerenes to be obtained at will, thus opening up a new avenue in the use of enantiomerically pure carbon nanostructures in materials science.

Inhaled antibiotics for the treatment of chronic bronchopulmonary Pseudomonas aeruginosa infection in cystic fibrosis: systematic review of randomised controlled trials.

INTRODUCTION: Inhaled antibiotics are probably the safest and most effective therapy for Pseudomonas aeruginosa chronic lung infection in cystic fibrosis (CF) patients. AREAS COVERED: To summarise the available evidence, a systematic review of the three currently available inhaled antibiotics (aztreonam lysine (AZLI), colistin (COL) and tobramycin (TOB)) was performed. The three AZLI placebo-controlled studies showed that the improvements in FEV1 and mean sputum P. aeruginosa density were statistically significant better than with placebo. The two COL placebo-controlled studies involved few patients but showed that COL was better than placebo in terms of maintenance of some pulmonary function parameters. The tobramycin inhalation solution (TIS) and tobramycin inhalation powder studies showed that the efficacy of both formulations was similar but significantly better than placebo. In the comparative studies, TIS showed more efficacy than COL solution, colistin inhalation powder showed non-inferiority to TIS and AZLI was superior to TIS. EXPERT OPINION: Placebo-controlled and comparative clinical trials have shown that clinical evidence of inhaled antibiotics is very different. The choice of treatment for each individual CF patient must be based on the features of the drug (clinical evidence on efficacy and safety), the inhalation system and the patient characteristics. Development of new inhaled antibiotics will allow new end points of efficacy and therapy regimens to be assessed.

[Methicillin-resistant Staphylococcus aureus in patients with cystic fibrosis]. / Staphylococcus aureus resistente a meticilina en pacientes adultos con fibrosis quística.

OBJECTIVE: To determine the prevalence of chronic colonization with methicillin-resistant Staphylococcus aureus (MRSA) in patients with cystic fibrosis, describe antibiotic sensitivity of the strains, and compare the patients' clinical characteristics with those of patients infected with methicillin-sensitive S. aureus (MSSA). PATIENTS AND METHODS: Patients with chronic S. aureus colonization were selected from a total of 50 patients with cystic fibrosis. Sputum samples were cultured according to standard microbiological procedures. Patients were considered to have chronic bronchial colonization if the same microorganism was isolated in 3 consecutive sputum samples, separated by an interval of at least 1 month. The following variables were compared between patients with MSSA (17) and MRSA (8): sex, body mass index, presence of pancreatic insufficiency, bacterial colonization, pulmonary function, Brasfield radiological score, Shwachman clinical score, and number of respiratory exacerbations in the previous year. RESULTS: The prevalence of infection by MRSA was 16%. All the MRSA strains were sensitive to vancomycin, teicoplanin, and linezolid. Patients with MRSA were older and had a larger number of respiratory exacerbations than patients with MSSA. CONCLUSIONS: There is a high percentage of colonization by MRSA in adult cystic fibrosis patients. Although the pathogenic role of this microorganism remains unclear, patients with MRSA had more frequent exacerbations and poorer lung function. Thus, infection control is important and patients should be adequately monitored.

[Nontuberculous mycobacterial infection in patients with cystic fibrosis: a multicenter prevalence study]. / Estudio multicéntrico de prevalencia de micobacterias ambientales en pacientes con fibrosis quística.

OBJECTIVE: To determine the prevalence of nontuberculous mycobacterial infection in patients with cystic fibrosis. PATIENTS AND METHODS: We performed a prospective study in which patients with cystic fibrosis were followed for 2 years; the patients were recruited from specialized units and were all over 6 years old. Sputum samples collected every 6 months were stained with auramine-rhodamine and cultures were prepared with a liquid and a solid medium. When stains or cultures were positive for nontuberculous mycobacteria, 1 or 2 additional sputum samples were obtained from the patients, who were monitored closely to assess the need for specific treatment. We assessed the following clinical variables: age, sex, presence of pancreatic insufficiency, use of aerosol antibiotic therapy, and long-term azithromycin and inhaled or oral corticosteroid therapies. RESULTS: A total of 220 patients (119 women) with a mean age of 22.62 years (range, 6-74 years) were enrolled; of these 23.6% were receiving azithromycin. We prepared 1303 sputum samples for mycobacterial growth (range per patient, 4-68 samples); 65 samples from a total of 17 patients (7.72%) were positive: 17 by auramine-rhodamine staining and 48 by culture. Eighty-eight culture samples were contaminated and Mycobacterium tuberculosis was not isolated in any of the cases. The mycobacteria isolated were M avium complex (n=10), M abscessus (n=6), and M fortuitum (n=1). Two or more positive cultures were obtained in 9 patients, 5 of whom experienced clinical deterioration and were prescribed specific treatment. No significant differences in clinical variables were found between patients with nontuberculous mycobacteria and those without. CONCLUSIONS: The prevalence of nontuberculous mycobacterial infection in patients with cystic fibrosis was not very high (7.72%), perhaps because azithromycin interfered with the growth of these bacteria. Patients with repeat isolations of mycobacteria should be monitored closely.

[Isolation of Nocardia species in patients with cystic fibrosis]. / Aislamiento de Nocardia en pacientes con fibrosis quística.

The isolation of Nocardia species from the respiratory secretions of patients with cystic fibrosis presents problems with important clinical implications. From the sputum culture of a total of 387 patients with cystic fibrosis, Nocardia species was isolated in 9 cases (2%; 8 females and 1 male) with a mean (SD) age of 17 (7) years. Sixty-seven percent of the patients were asymptomatic and no relevant radiographic or analytical changes were detected. In only 3 patients was of Nocardia species isolated again in successive samples. Two patients were not treated, 7 were treated with cotrimoxazole and 3 with minocycline; in 2 cases therapy was intravenous. After a mean follow-up of 48 (33) months, all patients had improved. Isolation of Nocardia species from the secretions of patients with cystic fibrosis does not necessarily imply infection and the need for treatment should be assessed on an individual basis.